Portable computers, colloquially referred to as "laptop" or "notebook" computers, have increased in power, speed, and memory capacity to the point where they offer functionality comparable to that of desktop-style personal computers. However, because portable computers have been designed for small size and low weight, their keyboards and displays have been limited in size, making the portable computers less convenient to use.
Also, since portable computers are designed for stand-alone use, they obtain operational power from either rechargeable battery packs for full stand-alone use, or AC power for use conveniently close to power outlets. While a portable computer is in use on AC power, it takes advantage of the available AC power and recharges the battery pack. Alternatively, a battery pack can be removed from the portable computer and charged separately.
Accordingly, portable computers' features and accessories have been designed with suitable interfaces to allow a user to use the same large-size displays and full-size keyboards as would normally be used with a desktop machine. In particular, docking stations have been developed, to hold all of the electrical connections between the keyboard, display, network connection, etc., with the computer. Docking stations also are designed to plug into AC power, and to provide that power to the portable computer. Thus, all a user has to do is "dock" the portable computer with the docking station, and the computer is ready to directly interface with all of the peripherals.
It will be understood that there must be physical and electrical compatibility between the portable computer and its docking station. However, portable computers vary considerably in size, configuration, etc., even within a given manufacturer's line. Also, battery packs for different personal computers vary in physical size, charge holding capacity, chemical formulation (e.g., lithium, nickel-cadmium), and electrical recharge specifications such as current limit values.
Thus, conventionally it has been necessary for a portable computer manufacturer to provide either (i) a whole line of functionally identical but physically different docking stations and battery chargers, commensurate with its line of portable computers, (ii) a menagerie of adapters, or (iii) docking stations which are mechanically complex (and expensive) enough to accommodate all possible variations and permutations of portable computers and batteries. Further, it has been necessary for the manufacturer to upgrade or modify the docking stations and/or adapters when the manufacturer develops a new model, or new line, of portable computers.
This multiplicity of different configurations has disadvantageously required manufacturers to many different models, instead of a more cost-efficient, higher-volume single model compatible with many different portable computer models. Design and manufacturing costs, as well as inventory controls and administrative costs, have been disadvantageously high.
The need for battery charging capability has added a further dimension to the problem of designing docking stations which combine user-desired functionality and manufacturer-desired low cost, versatility, and compatibility.